1. Field of Invention
The present invention relates to a stabilization band and or a ring assembly for aligning a projectile in a gun tube. More specifically, the invention relates to a double ramped, saboted, kinetic energy projectile assembly which constitutes an improvement for modern sabot designs which automatically align an assembly in the gun tube and a method related thereto.
2. Description of the Prior Art
One of the most efficient sabot assembly presently used to launch a kinetic energy projectile from a high performance gun is one constructed using the double ramp principle. An example is U.S. Pat. No. 4,936,220 to Bruce P. Burns, et al. which discloses a double-ramp sabot having a rear ramp 17, a central bulkhead 22 with an obturator 26, and a forward ramp 19 with a forward scoop 18. Other examples are U.S. Pat. Nos. 4,284,008 and 4,372,217 to Richard D. Kirkendall, et al. which disclose a sabot having a double configuration and a centrally positioned obturator.
Typical assemblages include a shell casing, propellant/ignition system, and a projectile. The shell casing may be fixed to or be separate from the projectile. The projectile either as a discrete element or as part of an assembly with the shell casing is normally inserted into the gun barrel through a rear opening mechanism or breech. The breech is closed, the propellant charge ignited and the projectile is propelled via the expansion of combustive products through the gun barrel until it exits the barrel at its muzzle. In order to insert or chamber the projectile there must inherently be clearances between the projectile and the gun barrel. A stabilizating band device on the projectile commonly know as an obturator provides a mechanism to maintain the combustive gases at or behind the projectile by providing a seal between the projectile and the wall of the gun barrel. Other than this sealing mechanism there is no continuous radial connection or contact between the projectile and the gun barrel. In a double ramp sabot the front bore-rider fulfills two functions. Firstly, after the projectile's exit from the gun barrel, the front bore-rider aids in sabot discard. Secondly, and more importantly, in regard to the present invention the front bore-rider provides support to the projectile assembly while it is in the bore. The bore rider's surface which makes contact with the gun wall may be an integral part of the sabot or an insert. The contacting surface is commonly cylindrically shaped and of a lesser diameter than that of the inner most surface of the gun barrel. This feature allows the projectile assembly to be inserted into the gun and reduces any pressurization within the saddle region of the sabot if there is leakage around the obturator. However, the clearance necessary for the operation of this type of bore-rider has negative effects. The clearances allow the projectile assembly to be positioned in the gun tube noncencentrically and noncolinearly with respect to the center line axis of the gun barrel. The actual position of the projectile with respect to the gun tube depends upon many factors and accumulated tolerances, gun tube wear, erosion, thermal expansion, and manufacturing quality. The initial position and possible misalignment tends to affect the accuracy of the projectile's impact with a target.
3. Advantages over the Prior Art
The present invention prevents the projectile from being initially positioned out of alignment relative to the gun tube's center line. It also has the ability to prevent the projectile from becoming cocked, or misaligned, as it travels down the gun tube's length. Finally, the present invention allows propulsion gases, which may escape past the obturator, to move forward of the projectile assembly.